VIENNA - Satellite images of an Iranian military facility appear to show trucks and earth-moving vehicles, indicating an attempted cleanup of radioactive traces possibly left by tests of a nuclear weapon trigger, diplomats said Wednesday.
Comments from the diplomats, all nuclear experts accredited to the International Atomic Energy Agency, could add to the growing international pressure on Iran over its nuclear program, which Tehran insists is for peaceful purposes. While the United States and the European Union back a sanctions-heavy approach, Israel has warned that it may resort to a preemptive strike against Iran’s nuclear facilities to prevent it from obtaining atomic weapons.
Two of the diplomats said crews at the Parchin military site may be trying to erase evidence of tests of a small experimental neutron device used to set off a nuclear explosion. A third diplomat could not confirm that but said any attempt to trigger a so-called neutron initiator could only be in the context of trying to develop nuclear arms.
The diplomats said they suspect attempts at sanitization because some of the vehicles appeared to be suited to carting off soil.
The images, provided by member countries to the atomic agency, the United Nations’ nuclear watchdog, are recent and constantly updated, one of the diplomats said. The diplomats all requested anonymity because they were not authorized to discuss the information.
In November, the agency said Parchin appeared to be the site of experiments with conventional high explosives meant to initiate a nuclear chain reaction. It did not mention a neutron initiator as part of those tests, but in a separate section cited an unnamed member nation as saying Iran may have experimented with a neutron initiator, without going into detail or naming a location for such work.
In contrast, the intelligence information shared by the two diplomats linked the high-explosives work directly to setting off a neutron initiator at Parchin.
Iran has previously attempted to clean up sites considered suspicious by world powers.
Iran razed the Lavizan Shian complex in northern Iran before allowing inspectors to visit the suspected repository of military procured equipment that could be used in a nuclear weapons program. Tehran said the site was demolished to make way for a park, but five years ago inspectors found traces of uranium enriched to or near the level used in making the core of nuclear warheads.
The Iranians also embarked on an extensive redo at Kalay-e Electric Co., just west of Tehran, before inspectors were given access nine years ago. Samples taken from Kalay-e showed traces of enriched uranium, though at levels substantially below warhead grade.
One official from an International Atomic Energy Agency member country said the Parchin neutron initiator experiments were conducted between 2003 and 2010. Another said any such tests were closer to 2003, adding it was not clear whether they were successful.
The timing is important.
US intelligence officials say they generally stand by a 2007 assessment that Iran stopped comprehensive secret work on developing nuclear arms in 2003. But Britain, France, Germany, Israel, and other US allies think such activities have continued, a view shared by the energy agency.
Iran vehemently denies allegations that it conducted any research and development into atomic weapons and says its nuclear activities are meant purely to generate power or for research.
Asked for comment, Ali Asghar Soltanieh, Iran’s chief delegate to the atomic energy agency, said he would not discuss any nuclear issues until after he delivered his statement to the agency’s 35-nation board meeting Thursday.
Agency officials also said they could not comment.